Motion-multiplying gear for hydraulic lifts.



J. J. BOYLE. MOTION MULTIPLYING GEAR FOB HYDRAULIC LIFTS.

APPLICATION FILED 001a, 1910.

1,07 1,466. Patented Aug. 26, 1913.

2 SHEETS-SHEET 1.

Y J. J. BOYLE.

MOTION MULTIPLYING GEAR FOR HYDRAULIO LIFTS.

APPLICATION FILED OUT. 8, 1910.

1,071 ,466, Patented Aug. 26, 1913.

2 SHEETS-SHEET z.

JOHN JAMES BOYLE, OF FLIXTON, NEAR MANCHESTER, ENGLAND.

MOTION-MULTIILYING GEAR FOR HYDRAULIC LIFTS.

Specification of Letters Patent.

Patented Aug. 26,1913.

Application filed October 8, 1910. Serial No. 586,038.

To all whom it may concern Be it known that I, JOHN J AMES BOYLE, a subject of the King of Great Britain and Ireland, and resident of-Flixton, near Manchester, England, have invented certain new and useful Improvements in Motion-Multiplying Gears for Hydraulic Lifts, of which the following is a specification.

These improvements refer to hydraulic lifting apparatus and the motion-multiplying or accelerating mechanism used'therewith for increasing the movement of the object being raised relatively to the movement of the hydraulic ram, the object of the invention being mainly to obtain the desired acceleration of movement without the friction, strain and wear present with existing gear and thereby allow of less power being used for working the apparatus.

According to the invention, and as applied to an ordinary hoist, use is made of a drum having different diameters, and the central part of the drum being of larger diameter than the outer parts. To each of the smaller diameters of the drum is connected one end of a wire rope, the other end of which, after coiling around the drum while the drum is at or near the top of the hoist, is connected to the cross head of the hydraulic ram fixed at or near the bottom of the hoist. To a beam or other suitable fixture at the top of the hoist is connected one end of a further rope, which, after coiling around the said larger diameter of the drum and extending upward and over a carrier pulley at the top of the hoist, extends downward and is connected to the hoisting element. For safety purposes there may be two ropes connected to the beam and cage, the larger drum and pulley being sufficiently wide. The hoisting element when unloaded will slightly overbalance the weight of the drum. With the drum at the top of the hoist, the hoisting element at its lowest point and the plunger of the hydraulic ram at the end of its inward stroke, the effect of admitting water to the ram under pressure is to cause the ropes connected with its cross-head to exert a downward pull and thereby roll the drum downward. A further effect is to cause the drum to exert a pull on the rope or ropes passing over the guide pulley, and thus raise the hoisting element.

In applying the invention to horizontal hoisting gear, a drum having two large and three small diameters is used and the drum rolls along a horizontal track. One of the small diameters is between the two large diameters and to the part of smaller diameter are secured the ends of a further rope, which after passing over guide pulleys extends down to a weighted hoisting hook, the weight of which is such as to return the drum as the ram moves inward.

Upon the accompanying drawings, Figure 1 illustrates a side elevation, Fig. 2 a front elevation, and Fig. 3 a plan of an ordinary hydraulic hoist or lift with the invention shown applied thereto. Figs. 4 and 5 illustrate a side elevation and plan respectively of a hoisting gear in which the ram and drum are designed to work in a horizontal direction.

Referring to Figs. 1, 2 and 3, a is the large diameter of the drum and b, b the two small diameters of the drum, one on each side of the large diameter. 0, a are the ropes secured to the beam cl at one end and the hoisting element is at the other end, such ropes passing once or twice around the part a of the drum and over the guide pulley c.

f, f are the further ropes respectively connected at one end to one of the small parts of the drum and at the other end connected to the cross-head g of the plunger h of the hydraulic ram 7'. Y

The drum is designed to run in rolled joist or like guides e, and therefore out of the path of the hoisting element 7c. To allow of proper movements of the ropes the pulley c is arranged diagonally, see Fig. 3.

Referring to Figs. 4L and 5, a, a are the large diameters of the drum, Z), Z) and Z the small diameters of the drum, the part Z be ing central to the parts a, a. c, 0 are the ropes connected at one end to and coiled around the parts a, a and to a fixed object at the other end. f, f are the ropes respectively connected to the parts 6, b at one end, and to the cross-head g of the plunger h of the ram cylinder 7' at the other end. an is a rope both ends of which are connected to the part Z of the drum, while within the loop formed by such rope, outside the building, is a weighted hook. This rope passes over guide pulleys projecting beyond the side of the building. As the plunger 72. moves out of the ram cylinder j, the ropes f, f exert a pull on the parts Z), Z) and owing to. the resistance offered by the ropes c, c, the parts a, a roll along the track on which they lie toward the ram. In so doing a pull is ex erted on the rope m, which is wound upon the part Z, and thus raises the object secured to the hoisting hook. The hook is weighted to an extent which insures of the hook lowering when unloaded under the run in of the plunger h.

hat I claim is:

1. In motion-multiplying gears for hoisting mechanism, a hoist structure, a hoisting element, a hydraulic ram, a drum of slightly varying diameters, ropes connected to the smaller diameter of the drum at one end and at their other end connected to the plunger of the hydraulic ram, further ropes connected at one end to the hoist structure and coiled around the larger diameter of the drum whereby the drum is given a constantly changing fulcrum on its larger diameter while the ram plunger, through the other ropes, moves the drum toward the rain, and means whereby on the drum being moved toward the ram the hoisting element is given an upward movement, as set forth.

2. In motion-multiplying gears for hoisting mechanism, a hydraulic ram, a hoist structure and cage, a drum having different diameters, ropes connected to the smaller diameter oi the drum at one end and to the ram at the other end, and further ropes connected to the larger diameter of the drum at one end and to the hoist structure at the other end, a guide pulley, further rope-s co11- nected to the drums which pass over the pulley and are also connected to the hoisting element, substantially as herein set forth.

In witness whereof I have hereunto set my hand in the presence of tWo witnesses.

JOHN JAMES BOYLE.

lVitnesses F. G. PENNINGTON, F. J. MEREDITH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. G. 

